With the development of Internet and electronic technologies, mobile client devices such as smart phones, tablet personal computers (PCs), e-book readers and ultrabooks have been widely applied in the daily lives of users. To be sure, such devices have become the first-choice devices for entertainment, education, and work. Often, these devices are used in a collaborative nature, in which users perform tasks and interact with one another through online gaming, crowdsourcing, etc.
Conventional methods of transferring tasks performed on mobile client devices are inadequate or inconvenient for users (for example, transferring control of an online game, or transferring work on a crowdsourcing project). For example, conventional methods of transferring tasks do not allow easy identification of those who are candidates to resume performance of the task. Conventional methods also do not conveniently notify such candidates that their help is desired.